共查询到20条相似文献,搜索用时 31 毫秒
1.
Reactive oxygen species (ROS) can exhibit negative and benign traits. In plants, ROS levels increase markedly during periods of environmental stress, and defense against pathogen attack. ROS form naturally as a by-product of normal oxygen metabolism, and evenly play an essential role in cell growth. The short ROS lifespan makes them ideal molecules to act in cell signaling, a role they share in both plants and animals. A particular plant organism, the pollen grain, may closely interact with human mucosa and an allergic inflammatory response often results. Pollen grain ROS represent a first, crucial signal which primes and magnifies a cascade of events in the allergic response. 相似文献
2.
Pathogen-induced elicitin production in transgenic tobacco generates a hypersensitive response and nonspecific disease resistance. 总被引:22,自引:0,他引:22
H Keller N Pamboukdjian M Ponchet A Poupet R Delon J L Verrier D Roby P Ricci 《The Plant cell》1999,11(2):223-235
The rapid and effective activation of disease resistance responses is essential for plant defense against pathogen attack. These responses are initiated when pathogen-derived molecules (elicitors) are recognized by the host. We have developed a strategy for creating novel disease resistance traits whereby transgenic plants respond to infection by a virulent pathogen with the production of an elicitor. To this end, we generated transgenic tobacco plants harboring a fusion between the pathogen-inducible tobacco hsr 203J gene promoter and a Phytophthora cryptogea gene encoding the highly active elicitor cryptogein. Under noninduced conditions, the transgene was silent, and no cryptogein could be detected in the transgenic plants. In contrast, infection by the virulent fungus P. parasitica var nicotianae stimulated cryptogein production that coincided with the fast induction of several defense genes at and around the infection sites. Induced elicitor production resulted in a localized necrosis that resembled a P. cryptogea-induced hypersensitive response and that restricted further growth of the pathogen. The transgenic plants displayed enhanced resistance to fungal pathogens that were unrelated to Phytophthora species, such as Thielaviopsis basicola, Erysiphe cichoracearum, and Botrytis cinerea. Thus, broad-spectrum disease resistance of a plant can be generated without the constitutive synthesis of a transgene product. 相似文献
3.
Agricultural crops worldwide suffer from a vast array of fungal diseases which cause severe yield losses. Upon interaction
with a pathogen, plants initiate a complex network of defense mechanisms, among which is a dramatic increase in chitinase
activity. Chitinases are capable of hydrolyzing chitin-containing fungal cell walls and are therefore thought to play a major
role in the plant’s response. One of the strategies to increase plant tolerance to fungal pathogens is the constitutive
overexpression of proteins involved in plant-defense mechanisms. The level of protection observed in transgenic plants harboring
heterologous chitinase genes varies, depending on the particular combination of enzyme, plant and pathogen tested. Nevertheless,
most of these transgenic plants exhibit increased tolerance to fungal diseases relative to their non-transgenic counterparts.
The combined expression of chitinases with other plant-defense proteins such as glucanases and ribosome-inactivating proteins
further enhances the plant’s resistance to fungal attack.
Received 29 January 1997/ Accepted in revised form 01 July 1997 相似文献
4.
Accumulation of reactive oxygen species (ROS) is an oxidative stress to which cells respond by activating various defense mechanisms or, finally, by dying. At low levels, however, ROS act as signaling molecules in various intracellular processes. Autophagy, a process by which eukaryotic cells degrade and recycle macromolecules and organelles, has an important role in the cellular response to oxidative stress. Here, we review recent reports suggesting a regulatory role for ROS of mitochondrial origin as signaling molecules in autophagy, leading, under different circumstances, to either survival or cell death. We then discuss the relationship between mitochondria and autophagosomes and propose that mitochondria have an essential role in autophagosome biogenesis. 相似文献
5.
Availability of complete Arabidopsis(Arabidopsis thaliana) and rice(Oryza sativa) genome sequences, together with molecular recourses of functional genomics and proteomics have revolutionized our understanding
of reactive oxygen species (ROS) signalling network mediating disease resistance in plants. So far, ROS have been associated
with aging, cellular and molecular alteration in animal and plant cells. Recently, concluding evidences suggest that ROS network
is essential to induce disease resistance and even to mediate resistance to multiple stresses in plants. ROS are obligatory
by-products emerging as a result of normal metabolic reactions. They have the potential to be both beneficial and harmful
to cellular metabolism. Their dual effects on metabolic reactions are dosage specific. In this review we focus our attention
on cellular ROS level to trigger beneficial effects on plant cells responding to pathogen attack. By exploring the research
related contributions coupled with data of targeted gene disruption, and RNA interference approaches, we show here that ROS
are ubiquitous molecules of redox-pathways that play a crucial role in plant defence mechanism. The molecular prerequisites
of ROS network to activate plant defence system in response to pathogen infections are here underlined. Bioinformatic tools
are now available to scientists for high throughput analysis of cellular metabolisms. These tools are used to illustrate crucial
ROS-related genes that are involved in the defence mechanism of plants. The review describes also the emerging findings of
ROS network pathways to modulate multiple stress resistance in plants. 相似文献
6.
P. Azizi S. N. A. Abdullah N. Nejat M. Maziah M. M. Hanafi 《Critical reviews in biotechnology》2016,36(1):165-174
The blast fungus, Magnaporthe oryzae, causes serious disease on a wide variety of grasses including rice, wheat and barley. The recognition of pathogens is an amazing ability of plants including strategies for displacing virulence effectors through the adaption of both conserved and variable pathogen elicitors. The pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity (ETI) were reported as two main innate immune responses in plants, where PTI gives basal resistance and ETI confers durable resistance. The PTI consists of extracellular surface receptors that are able to recognize PAMPs. PAMPs detect microbial features such as fungal chitin that complete a vital function during the organism’s life. In contrast, ETI is mediated by intracellular receptor molecules containing nucleotide-binding (NB) and leucine rich repeat (LRR) domains that specifically recognize effector proteins produced by the pathogen. To enhance crop resistance, understanding the host resistance mechanisms against pathogen infection strategies and having a deeper knowledge of innate immunity system are essential. This review summarizes the recent advances on the molecular mechanism of innate immunity systems of rice against M. oryzae. The discussion will be centered on the latest success reported in plant–pathogen interactions and integrated defense responses in rice. 相似文献
7.
Arabidopsis defense response against Fusarium oxysporum 总被引:1,自引:0,他引:1
The plant fungal pathogen Fusarium oxysporum (Fox) is the causal agent of root rot or wilt diseases in several plant species, including crops such as tomato (Solanum lycopersicum), banana (Musa sapientum) and asparagus (Asparagus officinalis). Colonization of plants by Fox leads to the necrosis of the infected tissues, a subsequent collapse of vascular vessels and decay of the plant. Plant resistance to Fox appears to be monogenic or oligogenic depending on the host. Perception of Fox by plants follows the concept of elicitor-induced immune response, which in turn activates several plant defense signaling pathways. Here, we review the Fox-derived elicitors identified so far and the interaction among the different signaling pathways mediating plant resistance to Fox. 相似文献
8.
Ved Prakash Kanchan Vishwakarma Vijay Pratap Singh Padmaja Rai Naleeni Ramawat Durgesh Kumar Tripathi Shivesh Sharma 《Physiologia plantarum》2020,168(2):473-489
Over the past decades the role of nitric oxide (NO) and reactive oxygen species (ROS) in signaling and cellular responses to stress has witnessed an exponential trend line. Despite advances in the subject, our knowledge of the role of NO and ROS as regulators of stress and plant growth and their implication in signaling pathways is still partial. The crosstalk between NO and ROS during root formation offers new domains to be explored, as it regulates several plant functions. Previous findings indicate that plants utilize these signaling molecules for regulating physiological responses and development. Depending upon cellular concentration, NO either can stimulate or impede root system architecture (RSA) by modulating enzymes through post-translational modifications. Similarly, the ROS signaling molecule network, in association with other hormonal signaling pathways, control the RSA. The spatial regulation of ROS controls cell growth and ROS determine primary root and act in concert with NO to promote lateral root primordia. NO and ROS are two central messenger molecules which act differentially to upregulate or downregulate the expression of genes pertaining to auxin synthesis and to the configuration of root architecture. The investigation concerning the contribution of donors and inhibitors of NO and ROS can further aid in deciphering their role in root development. With this background, this review provides comprehensive details about the effect and function of NO and ROS in the development of RSA. 相似文献
9.
Reactive oxygen species (ROS) are constantly produced in plants, as the metabolic by-products or as the signaling components in stress responses. High levels of ROS are harmful to plants. In contrast, ROS play important roles in plant physiology, including abiotic and biotic tolerance, development, and cellular signaling. Therefore, ROS production needs to be tightly regulated to balance their function. Respiratory burst oxidase homologue (RBOH) proteins, also known as plant nicotinamide adenine dinucleotide phosphate oxidases, are well studied enzymatic ROS-generating systems in plants. The regulatory mechanisms of RBOH-dependent ROS production in stress responses have been intensively studied. This has greatly advanced our knowledge of the mechanisms that regulate plant ROS production. This review attempts to integrate the regulatory mechanisms of RBOHD-dependent ROS production by discussing the recent advance. AtRBOHD-dependent ROS production could provide a valuable reference for studying ROS production in plant stress responses. 相似文献
10.
11.
Simranjeet Singh Vijay Kumar Dhriti Kapoor Sanjay Kumar Satyender Singh Daljeet Singh Dhanjal Shivika Datta Jastin Samuel Pinaki Dey Shanquan Wang Ram Prasad Joginder Singh 《Physiologia plantarum》2020,168(2):301-317
In the recent times, plants are facing certain types of environmental stresses, which give rise to formation of reactive oxygen species (ROS) such as hydroxyl radicals, hydrogen peroxides, superoxide anions and so on. These are required by the plants at low concentrations for signal transduction and at high concentrations, they repress plant root growth. Apart from the ROS activities, hydrogen sulfide (H2S) and nitric oxide (NO) have major contributions in regulating growth and developmental processes in plants, as they also play key roles as signaling molecules and act as chief plant immune defense mechanisms against various biotic as well as abiotic stresses. H2S and NO are the two pivotal gaseous messengers involved in growth, germination and improved tolerance in plants under stressed and non-stress conditions. H2S and NO mediate cell signaling in plants as a response to several abiotic stresses like temperature, heavy metal exposure, water and salinity. They alter gene expression levels to induce the synthesis of antioxidant enzymes, osmolytes and also trigger their interactions with each other. However, research has been limited to only cross adaptations and signal transductions. Understanding the change and mechanism of H2S and NO mediated cell signaling will broaden our knowledge on the various biochemical changes that occur in plant cells related to different stresses. A clear understanding of these molecules in various environmental stresses would help to confer biotechnological applications to protect plants against abiotic stresses and to improve crop productivity. 相似文献
12.
Forlani G Occhipinti A Bossi S Bertea CM Varese C Maffei ME 《Journal of plant physiology》2011,168(17):2041-2047
Plants react to microbial attack with a number of defense mechanisms, including the synthesis of volatile organic compounds (VOCs) and the production of reactive oxygen species (ROS). These responses are triggered by elicitors derived from either the cell surface of pathogens or the incomplete hydrolysis of the plant cell wall. Here we show the response of rice (Oryza sativa L., cv Gigante Vercelli) cell cultures following treatment with cell wall hydrolysates prepared from the rice blast Magnaporthe oryzae. Elicitation prompted the production of several plant VOCs, which were analyzed by stir bar sorptive extraction from both the liquid and head-space phase (SBSE and HSSE, respectively) and gas chromatography coupled to mass spectrometry (GC-MS) analysis. VOCs included alkanes, alkenes and long-chain alcohols as well as cinnamyl alcohol, myristicin, a sesquiterpene alcohol (caryolan-1-ol), 1-butanamide and 2-pentylfuran. The major released compounds, 1-octanol and 1-decanol, were found to induce ROS production in both elicited and non-elicited rice cells and showed fungistatic activity against the pathogen M. oryzae. The possible role of induced VOCs and ROS production in the plant-pathogen interaction is discussed. 相似文献
13.
植物中参与活性氧调控的基因网络 总被引:4,自引:0,他引:4
植物体内活性氧(reactive oxygen species,ROS)是氧化还原反应的必然副产物,具极高的活性和毒性,从而对细胞产生毒害。同时,活性氧作为信号分子对很多生理过程诸如植物生长发育、细胞程序化死亡及生物和非生物胁迫应答起调控作用。植物中ROS双重作用的协调机制目前尚不明确,确定的是细胞中ROS维持于稳定水平需要精细的调节。拟南芥中至少包括152个基因组成的网络参与ROS的调控,该网络具高度的灵活性和互补性。本文综述了ROS网络中鉴定的一些关键基因及细胞学定位和协同作用,ROS信号转导,尤其是叶绿体中ROS信号的调控。 相似文献
14.
15.
Aboveground fungal pathogens can substantially reduce biomass production in grasslands. However, we lack a mechanistic understanding of the drivers of fungal pathogen infection and impact. Using a grassland global change and biodiversity experiment we show that the trade‐off between plant growth and defense is the main determinant of infection incidence. In contrast, nitrogen addition only indirectly increased incidence via shifting plant communities towards faster growing species. Plant diversity did not decrease incidence, likely because spillover of generalist pathogens or dominance of susceptible plants counteracted negative diversity effects. A fungicide treatment increased plant biomass production and high levels of infection incidence were associated with reduced biomass. However, pathogen impact was context dependent and infection incidence reduced biomass more strongly in diverse communities. Our results show that a growth‐defense trade‐off is the key driver of pathogen incidence, but pathogen impact is determined by several mechanisms and may depend on pathogen community composition. 相似文献
16.
Plant immune systems effectively prevent infections caused by the majority of microbial pathogens that are encountered by plants. However, successful pathogens have evolved specialized strategies to suppress plant defense responses and induce disease susceptibility in otherwise resistant hosts. Recent advances reveal that phytopathogenic bacteria use type III effector proteins, toxins, and other factors to inhibit host defenses. Host processes that are targeted by bacteria include programmed cell death, cell wall-based defense, hormone signaling, the expression of defense genes, and other basal defenses. The discovery of plant defenses that are vulnerable to pathogen attack has provided new insights into mechanisms that are essential for both bacterial pathogenesis and plant disease resistance. 相似文献
17.
In most fungal pathogen–plant systems, a high level of sugars in plant tissues enhances plant resistance. Several hypotheses have been proposed to explain the mechanisms of “high-sugar resistance”. Sugars constitute the primary substrate providing energy and structural material for defense responses in plants, while they may also act as signal molecules interacting with the hormonal signaling network regulating the plant immune system. Sugars enhance oxidative burst at early stages of infection, increasing lignification of cell walls, stimulate the synthesis of flavonoids and induce certain PR proteins. Some sugars act as priming agents inducing higher plant resistance to pathogens. 相似文献
18.
Reactive oxygen species signaling and stomatal movement in plant responses to drought stress and pathogen attack 总被引:3,自引:0,他引:3
Junsheng Qi Chun-Peng Song Baoshan Wang Jianmin Zhou Jaakko Kangasj?rvi Jian-Kang Zhu Zhizhong Gong 《植物学报(英文版)》2018,(9)
Stomata, the pores formed by a pair of guard cells, are the main gateways for water transpiration and photosynthetic CO_2 exchange, as well as pathogen invasion in land plants. Guard cell movement is regulated by a combination of environmental factors, including water status, light, CO_2 levels and pathogen attack, as well as endogenous signals, such as abscisic acid and apoplastic reactive oxygen species(ROS). Under abiotic and bioticstress conditions, extracellular ROS are mainly produced by plasma membrane-localized NADPH oxidases, whereas intracellular ROS are produced in multiple organelles. These ROS form a sophisticated cellular signaling network, with the accumulation of apoplastic ROS an early hallmark of stomatal movement. Here, we review recent progress in understanding the molecular mechanisms of the ROS signaling network,primarily during drought stress and pathogen attack. We summarize the roles of apoplastic ROS in regulating stomatal movement, ABA and CO_2 signaling, and immunity responses.Finally, we discuss ROS accumulation and communication between organelles and cells. This information provides a conceptual framework for understanding how ROS signaling is integrated with various signaling pathways during plant responses to abiotic and biotic stress stimuli. 相似文献
19.
Gómez-Ariza J Campo S Rufat M Estopà M Messeguer J San Segundo B Coca M 《Molecular plant-microbe interactions : MPMI》2007,20(7):832-842
Expression of pathogenesis-related (PR) genes is part of the plant's natural defense response against pathogen attack. The PRms gene encodes a fungal-inducible PR protein from maize. Here, we demonstrate that expression of PRms in transgenic rice confers broad-spectrum protection against pathogens, including fungal (Magnaporthe oryzae, Fusarium verticillioides, and Helminthosporium oryzae) and bacterial (Erwinia chrysanthemi) pathogens. The PRms-mediated disease resistance in rice plants is associated with an enhanced capacity to express and activate the natural plant defense mechanisms. Thus, PRms rice plants display a basal level of expression of endogenous defense genes in the absence of the pathogen. PRms plants also exhibit stronger and quicker defense responses during pathogen infection. We also have found that sucrose accumulates at higher levels in leaves of PRms plants. Sucrose responsiveness of rice defense genes correlates with the pathogen-responsive priming of their expression in PRms rice plants. Moreover, pretreatment of rice plants with sucrose enhances resistance to M. oryzae infection. Together, these results support a sucrose-mediated priming of defense responses in PRms rice plants which results in broad-spectrum disease resistance. 相似文献
20.
Evidence for maintenance of sex by pathogens in plants 总被引:6,自引:0,他引:6
Busch JW Neiman M Koslow JM 《Evolution; international journal of organic evolution》2004,58(11):2584-2590
The predominance of outcrossing despite the substantial transmission advantage of self-fertilization remains a paradox. Theory suggests that selection can favor outcrossing if it enables the production of offspring that are less susceptible to pathogen attack than offspring produced via self-fertilization. Thus, if pathogen pressure is contributing to the maintenance of outcrossing in plants, there may be a positive correlation between the number of pathogen species attacking plant species and the outcrossing rate of the plant species. We tested this hypothesis by examining the association between outcrossing rate and the number of fungal pathogen species that attack a large, taxonomically diverse set of seed plants. We show that plant species attacked by more fungal pathogen species have higher outcrossing rates than plants with fewer enemies. This relationship persists after correcting for study bias among natural and agricultural species of plants. We also accounted for the nested hierarchy of relationships among plant lineages by conducting phylogenetically independent contrasts (PICs) within genera and families that were adequately represented in our dataset. A meta-analysis of the correlation between pathogen and outcrossing PICs shows that there is a positive correlation between pathogen species number and outcrossing rates. This pattern is consistent with the hypothesis that pathogen-mediated selection may contribute to the maintenance of outcrossing in species of seed plants. 相似文献